Syringe



M. NEVlN Aug., 18, 1931.

SYRINGE Filed sept. 2a, 1929 Mov( AT ORNEYS Patented Aug. 18, 1931 )PATENT oFFlcE MENDEL NEVIN, F BROOKLYN, NEW YORK SYINGE Application led September 28, 1929. Serial No. 395,855'.

Myy invention relates to improvements in syringes and while particularly adapted for use in connection with hypodermic syrin es' for injecting local anaesthetics and the li ze,

the same may nevertheless be found useful in connection with other types of syringes. The invention more particularly relates to that type of syringe inwhich the medicament is previously prepared in liquid form 1g and placed in ampules, the ampules as needed to be placed in the body of the syringe and the contents expelled therefrom.

rlhe main object of the invention is to.

provide an arrangement of this class which is more efficient in operation than those heretofore used. Further and more specific objects, features and advantages will more clearly appear from the detail description given below taken in connection with the accompanyiug sheet of drawings which forms a art of thisl specification. v eferring to the drawings, Fig. 1 is a section lthrough a hypodermic syringe embodying my invention in a preferred form thereof, the ampule therein having its tip broken off and the contents thereof partially ejected. Fig. 2 is a side view of 'one of the ampules in which themedicament is put up preparatory to use in the syringe. F ig. 3 is a 3o sectional detail of the rear end of the ampule and the forward end of the plunger whicl cooperates therewith.

Referring to Fig. 1, 3 represents a cylindrical barrel of a syringe adapted to hold the ampule 44. rlihe barrel 3is open at `opposite sides as indicated at 5 in order that the contents of the ampule in the syringe may be viewed therethrough from the outside. At its forward end there is screwed onto the barrel 3 a head 6 carrying a soft rubber seat 7 against which the end of the ampule 4 isV adapted to be seated and cushioned. A ring 8 screw-threaded Iinto the head 6 holds the seat 7 in osition. The head 6 is provided with a reduced screw-threaded extension 9 on which is adapted to be screwed a hub 10 of a hypodermic needle 11. The hub 10 is adapted to be screwed down upon a packing 12 held in place on the head. 6 by a ring member 13 screwed on the outer end of the head vided with a piston member 16 of rubber or other suitable composition. The piston member 16 closes and seals the rear end of the ampule as shown in Fig. 2. The ampules B5 previously prepared and containing the medicament as shown in Fig. 2 are drawn out at their opposite ends to form a reduced on tapered portion 17 which is sealed olf as as at 18 and this reduced portion is provided 70 with a constriction therein both external and internal forming a weakened end as indicated at 14, near the cylindrical body poriton of the ampule. The reduced portion is adapted to be broken ofl:` the body portion of 76 the ampule at 14', and for this purpose the same may be nicked or notched as with a file, at 14.

Rigidly secured to the barrel member 3 are finger grips 19 and removably attached to the rear end of the barrel 3 is a head 20 which head is provided with a bayonet slot 22 adapted to cooperate with a pin 21 fixed in the rear end of the barrel 3 so that the head 20 may be easily slipped over the rear end of the barrel 3 and forced forward thereon by turning the same so thatthe outer end of the pin 21 slides along the bayonet slot 22 thereby carrying the head 3 forward. Slidably mounted within the head 20 is a sleeve member 24 enlarged at its lower end as at 25. Acoil spring 26 located within the head 20 and bearing against the enlargement 25 tends `.to force the same toward the ampule 4 and resiliently engage the same so as to force 95 .the ampule 4 resiliently against its seat 7 at the opposite end. Slidably mounted in the sleeve member' 24 is a plunger member 26a carrying a plunger 27 which is unattached to but adapted to engage the piston 10| `als 16 in order to move the same lengthwise of the ampule and expel the contents thereof. The plunger member 26a is provided with a hand piece 28 and the enlargement 25 on the sleeve 24 is recessed at 29 in order to receive the plunger 27 when it is retracted and so that the plunger 27 may be entirely withdrawn from the am ule.

The body portion of t e ampule 4 is cylindrical in shape and the piston 16 is also cylindrical in shape and is provided with two circular grooves 30 extending circumferentially thereabout near the rear end of the piston (see Fig. 3) which grooves are preferably filled with glycerine or some other lubricating material. r1`he piston 16 is also provided with a circular recess 31 in its rear face which is engaged by the plunger 27. The depth of said recess 31 is relatively small as compared with the length of the piston 16, the side walls ofthe said recess 31 are substantially parallel to the line of movement of the piston 16, the bottom of said recess 31 extends substantially at right angles to the line of movement of the piston 16 and the plunger 27 is beveled off to form a frustroconical portion 32 adapted to engage within said recess, the smaller part of said frustroconical portion being of less diameter than the recess and the larger part of the frustroconical portion being of greater diameter than the recess whereby upon being forced into said recess vthe rear edge of the piston at 32 is forced outwardly against the inside of the ampule and it is found that as the plunger 32 is forced forward 4this makes an extremely tight 'oint between the piston and the ampule and liquid is prevented from being forced past the piston 16 and out at the rear of the ampule. That is, the forward face of the plunger 27 which engages within the recess 31 is of less diameter than said recess, while the rear portion of the plunger 27 is of larger diameter than said recess, whereby' the plunger acts to force the rear edge of the piston outwardly against the inside of the ampule as the plunger is forced into said recess and the piston forced forwardly in the ampule. This results in an extremely simple and efficient arrangement tending to prevent the liquid from being ejected or leaking past the piston 16 and out of the rear end of the ampule during the operation of the syringe.` This arrangement also tends to prevent the turning over of the piston 16 when considerable pressure is applied thereto by the plunger 27.

By drawing out the forward end of the ampule to form a reduced portion and providing a constriction, a weakened neck 14' therein near the body portion of the ampule,

this forms a weak point in the reduced portion near the body portion of the ampule which may be easily broken off and which in ordinary use will always be broken in substantially the same place so that the ampule after being broken olf may be inserted in the syringe barrel upon removal of the head 20, etc., and the broken end of the ampule at 14 will always come into substantially the same position in the head 6 when the head 20 of the syringe is replaced and the sleeve member 23 with the` spring 26 thereon acts to force the ampule 4 into position with itsfor- Ward end against the seat 7. lf the reduced portion 17 were broken at some other point nearer the tip 18, then, if the ampule be inserted in the syringe body, the reduced end would likely come in contact with the metallic portion of the head 6 as at 33 and thus prevent the forward end of the ampule from being properly seated against the packing seat 7 yso as to prevent leakage of the fluid back around the outside of the ampule. That is. said constriction is so positioned that the broken end of the ampule will be back of the passageway 15 and permit the end of the ampule to be sealed against the seat 7. In

other Words by providing a constriction as at 14 the users willinvariably be caused to break 0H the reduced portion 17 at the point 14 so that when so broken the ampule will be received in the syringe barrel 3 in its proper operative position. By permitting the ampule to be constricted at 14 both externally and internally the constriction may be formed in a more simple and eflicientmanner.

While have described my improvements in great detail and with respect to a preferred form thereof, I do not desire to be limited to such details and forms since many changes and modifications may be made and the invention embodied in widely different forms without departing from the spirit and scope thereof in its broader aspects. Hence I desire to cover all modifications, forms and embodiments coming within the language or scope of any one or more of the appended claims.

What I claim as new and desire to secure by Letters Patent, is:

1. The combination of an ampule tapered at one end onl the tapered end being sealed, a piston mem er closing and sealing the opposite end of the ampule and adapted to e moved lengthwise of the ampule to expel the contents thereof, said tapered portion having a constriction therein a holder for the ampule, a plunger carried by said holding means and adapted to operate said piston, said holding means having a head with a seat against which the reduced end of the ampule is adapted to be seated, said head having a assageway therethrough, aneedle attache to sald head and communicating with said passageway, the reduced portion of the ampule being adapted to be broken olf at said constriction, and said constriction being so positioned that the broken end of the ampule will lie back of said passageway and permit the a constriction therein, both external and internal, a holder for the ampule, a plunger carried by said holding means and adapted to operate said piston, said holding means having a head with a seat against which the reduced end of the ampule is adapted to be seated, means forcing the ampule against said seat independently of the plungersaid head having a passageway therethrough, a needle attached to said head and communicating with said passageway, the reduced portion of the ampule being adapted to be broken olf at said constriction, and said constriction being so positioned that the broken end of the ampule will lie back of said passageway and permit the end of the ampule to be seated against said seat, and said seat being composed of a resilient cushion having an unobstructed opening therethrough communicating with the passageway through the head.

3. The combination of a glass ampule tapered at one end only, the tapered end being sealed by the glass of the ampule itself, a

piston member closing and sealing the opposite end of the ampule, said piston member having a recess into which the head of the plunger lits to prevent the plunger coming in contact with the glass, said tapered portion having a weakened neck portion, a holder for vthe ampule, a plunger carried by said holder and adapted to operate said piston, said holder having a head with a seat against which the reduced end of the ampule is adapted to be seated, means forcing the ampule against said seat independently of. the plunger, said head having a' passageway therethrough, a needle attached to said head and communicating with said passageway, the reduced portion ofthe ampule being adapted to be broken off at said neck, and said neck being so positioned that the broken end of the ampule will lie back of said passageway and permit the end of the ampule to be seated against saidseat.

4. The combination of an ampule tapered at one end only, the tapered end being sealed, a piston member closing and sealing the opposite end of the ampule and adapt-ed to be moved lengthwise of the ampule to expel the contents thereof, said tapered portion having a weakened portion therein, a holder for the ampule, a plunger carried by said holding means and adapted to operate said piston, said holding means having a head with a seat against which the reduced end of the ampule is adapted to be seated, said head having a passageway therethrough, a needle attached to said head and communicating with said passageway, the reduced portion of the ampule being adapted to be broken ol at said weakened portion, and said weakened portion being so positioned that the broken end of the ampule will lie back of said passageway and permit the end of the ampule to be sea-ted against said seat.

In testimony `whereof I have signed my name to this specification.

MENDEL NEVIN. .75 

